On The Road Again: Assessing The Use Of Roadsides As Wildlife Corridors For Gopher Tortoises (Gopherus Polyphemus)

Small populations resulting from the impacts of habitat fragmentation are prone to increased risks of extinction because of a lack of population connectivity. Roads increase habitat fragmentation, but properly managed roadsides may be able to function as wildlife corridors. Here we use radiotelemetry to observe movement patterns of Gopher Tortoises (Gopherus polyphemus) along potential roadside corridors at the John F. Kennedy Space Center (KSC) in Florida, USA, to determine if tortoises use roadsides as movement pathways between larger habitat patches or as residential habitat. Additionally, we translocated tortoises to study the feasibility of roadsides to function as movement corridors. We found that roadsides are not used as a movement pathway but rather as an apparent long-term residential habitat. Only one tortoise was observed exiting the roadside corridor, and minimum convex polygon (MCP) home range sizes and distances traveled remain similar to those exhibited by tortoises in larger habitat patches. Following translocation, we observed a failure to return home, either by direct paths or by corridor use, for all but one tortoise. Instead, most tortoises remained along roadsides after only a brief period of exploration. Overall, we find that roadsides act as independent, residential habitat instead of as a movement corridor. Future studies should focus on understanding the actual suitability of roadsides, as they may function as ecological traps given their attractiveness but high risk of mortality. While we urge caution, current management should treat roadsides as residential locations for Gopher Tortoises and focus on reducing road mortality

Stopped Dead In Their Tracks: The Impact Of Railways On Gopher Tortoise (Gopherus Polyphemus) Movement And Behavior

Habitat fragmentation is one of the leading causes of biodiversity decline and most commonly results from urbanization and construction of transportation infrastructure. Roads are known to negatively impact species, but railways can often cause similar effects. Certain taxa, such as turtles and tortoises, are more vulnerable to railways than others due to limitations in mobility. We studied the impact of rails on the movement and behavior of Gopher Tortoises (Gopherus polyphemus), a threatened, highly terrestrial species likely in frequent contact with railways. First, we used radio-telemetry to determine the frequency of railway crossings and compared this to correlated random walk (CRW) simulations to assess if tortoises were crossing the rails less frequently than is expected by unconstrained movement. Second, we placed tortoises into the railway and measured behavior for one hour to assess crossing ability. Lastly, we tested whether trenches dug underneath the rails could allow safe passage for tortoises. We found that railways impacted the movement of Gopher Tortoises. Gopher Tortoises crossed the railway less often than what would be expected by unhindered movement for five of our ten tortoises tracked. During behavioral trials, 0 of 24 tortoises placed within the railways were capable of escaping from the rails. Using game cameras, we detected tortoises using trenches dug underneath the rails and between the ties 68 times over the course of a single summer. For minimal financial cost, the trenches facilitated tortoise movement across the railway, maintained full rail functionality, and created an escape route for individuals that were trapped between the rails, and thus should be implemented as a mitigation strategy. Given the thousands of km of railways around the world, we recommend future studies focus on the new field of rail ecology

On the road again: Assessing the use of roadsides as wildlife corridors for Gopher Tortoises (Gopherus polyphemus)

Tortoise and Telemetry data along with the R script used to trim and analyze the data

Data for: Stopped dead in their tracks: The impact of railways on Testudine movement and behavior

This dataset includes .csv spreadsheets (x4) of raw data collected for analysis in the manuscript Stopped dead in their tracks: The impacts of railways on Testudine movement and behavior and the R coding used to analyze the data. The files are as follows: 1. Behavior.csv: This contains the raw data obtained from continuous focal behavioral sampling of Gopher Tortoises placed inside of railways. 2. CameraData.xlsx: This contains the raw data obtained from game camera photos taken at a trench dug underneath an inactive railway as a management strategy to reduce their impacts. 3. GameCameras_Railway.zip: This contains all the game camera photos taken along the railway. 4. StoppedDeadintheirTracks.R: This file is the R script used to analyze the data for all parts of this study. 5. Telemetry.csv: This contains the raw data obtained from radio-telemetry of Gopher Tortoises at Kennedy Space Center. The R code thins this data to those found around railways for analysis. 6. Tortoises.csv: This contains the unique individual tortoises captured and marked at Kennedy Space Center. The R code this this data to look at those only found around the railways or used in the behavioral samplin